Air Pollution Stunts Cognition

Particulates in the air can cause impaired learning and depression in mice.

By Tia Ghose | July 6, 2011

Smoke stacksADIE REED VIA FLICKR

Air pollution has already been implicated in a variety of human diseases, including asthma, heart disease, and stroke. Now, new data in mice suggests that the air-borne particulates we breathe in throughout our lives may also slow learning and cause depression, according to a study published Tuesday (July 5) in Molecular Psychiatry.

“This is a really important study and they did a really nice job,” said Staci Bilbo, a neuroimmunologist at Duke University, who was not involved in the research. “It really is one of the first to show a lifetime exposure effect” of [pollution].

Several studies have shown that normal particulate matter in the air can trigger inflammation that leads to respiratory and cardiovascular problems. Previous research has also linked unnaturally high doses of air pollution to short-term changes in brain function in animals. But relatively little was known about how normal levels of pollution affect the brain long-term.

Laura Fonken, a neuroscientist at Ohio State University, and her colleagues suspected that even moderate levels of air pollution may also harm the brain. The researchers concentrated particulate matter made up of automobile, power plant, and factory emissions from ambient air in Columbus, Ohio, and created a new mixture with levels of pollution similar to that seen in countries with high levels of pollution, such as China and India.

The researchers then exposed one group of male mice to the dirty air for 6 hours a day, five days a week, while providing another group with filtered air. After ten months, the mice went through a battery of tests, including a maze test that assessed learning and memory, and a forced swim test that measured levels of despair. Mice that breathed the polluted air were slower to learn the maze’s escape route and gave up swimming more quickly, a sign of depression.

When the group analyzed the brains of the mice, they found the hippocampus had fewer connections between neurons and high levels of cytokines and TNF-alpha, molecules known to cause inflammation.

“This suggests that there may be some mild, chronic, low-grade inflammation in the mice exposed to particulate matter,” Fonken said. The researchers think the inflammation may be reducing the neuronal connections and in turn lowering the rats’ cognitive abilities.

But the study focused exclusively on male mice, so it remains to be seen whether the same effects will hold true in female mice, as well as other species. “They didn’t study females, which I was very disappointed to see, because we’re half the population,” said Stacy Bilbo, a neuroscientist at Duke University in Durham, N.C. who was not involved in the study. Females (both the mouse and human varieties) are also more prone to depression, she said.

Furthermore, significant differences between the nasal tracts and lungs of rodents versus humans may affect how the species respond to inhaled pollution, Bilbo added, and thus human studies are needed—and soon—to really understand how air pollution is affecting people. “I think that we really need to start to understand what it is that we’re doing to ourselves.”

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What the action of the human kind destroys, science recovers. The discovery of the neuroplasticity, the ability of the brain to create and develop neurons and connections to decrease the natural cognitive decline and improve the brain capacity, has been breakthrough over the past decades. It created a new form of training - the brain training programs. When scientifically validated, these programs may change your life for the better. I recommend one that is available online, it is for free: CogniFit. http://www.cognifit.com/

Well, is it all that bad that cognition is reduced? We do need a new class of workers under the newly emerging world order of international corporations---drones that can be taught to do simple repetitive meaningless jobs that those with normal intelligence would go nuts at. As noted, the Chinese are getting fed up with sweat shop jobs and high costs of living, so a replacement cadre is warranted to keep profits up. My constituents want to see cheap labor for their factories. If its good for business and corporate profits, I assume we can write new legislation creating a sub-class of semi-humans who would not enjoy the usual Constitutional protections, and the US Supreme Court should see the wisdom of this; they certainly have been cooperative with corporate needs thus far. Afterall, the court did find that catchup was a vegetable for purposes of school lunches, thus saving untold sums so other products could be purchased, even though the kids in these schools had allergies to these other products.

After all, those near pollution sources are usually in what some consider the lower socio-economic classes and seem to do poorly anyway in schools. Look at all the savings school districts could get by not having to spend tax dollars on a fuller education. If you look at this issue in a positive way, I'm sure you will begin to appreciate my points.

What the action of the human kind destroys, science recovers. The discovery of the neuroplasticity, the ability of the brain to create and develop neurons and connections to decrease the natural cognitive decline and improve the brain capacity, has been breakthrough over the past decades. It created a new form of training - the brain training programs. When scientifically validated, these programs may change your life for the better. I recommend one that is available online, it is for free: CogniFit. http://www.cognifit.com/

Well, is it all that bad that cognition is reduced? We do need a new class of workers under the newly emerging world order of international corporations---drones that can be taught to do simple repetitive meaningless jobs that those with normal intelligence would go nuts at. As noted, the Chinese are getting fed up with sweat shop jobs and high costs of living, so a replacement cadre is warranted to keep profits up. My constituents want to see cheap labor for their factories. If its good for business and corporate profits, I assume we can write new legislation creating a sub-class of semi-humans who would not enjoy the usual Constitutional protections, and the US Supreme Court should see the wisdom of this; they certainly have been cooperative with corporate needs thus far. Afterall, the court did find that catchup was a vegetable for purposes of school lunches, thus saving untold sums so other products could be purchased, even though the kids in these schools had allergies to these other products.

After all, those near pollution sources are usually in what some consider the lower socio-economic classes and seem to do poorly anyway in schools. Look at all the savings school districts could get by not having to spend tax dollars on a fuller education. If you look at this issue in a positive way, I'm sure you will begin to appreciate my points.

What the action of the human kind destroys, science recovers. The discovery of the neuroplasticity, the ability of the brain to create and develop neurons and connections to decrease the natural cognitive decline and improve the brain capacity, has been breakthrough over the past decades. It created a new form of training - the brain training programs. When scientifically validated, these programs may change your life for the better. I recommend one that is available online, it is for free: CogniFit. http://www.cognifit.com/

Well, is it all that bad that cognition is reduced? We do need a new class of workers under the newly emerging world order of international corporations---drones that can be taught to do simple repetitive meaningless jobs that those with normal intelligence would go nuts at. As noted, the Chinese are getting fed up with sweat shop jobs and high costs of living, so a replacement cadre is warranted to keep profits up. My constituents want to see cheap labor for their factories. If its good for business and corporate profits, I assume we can write new legislation creating a sub-class of semi-humans who would not enjoy the usual Constitutional protections, and the US Supreme Court should see the wisdom of this; they certainly have been cooperative with corporate needs thus far. Afterall, the court did find that catchup was a vegetable for purposes of school lunches, thus saving untold sums so other products could be purchased, even though the kids in these schools had allergies to these other products.

After all, those near pollution sources are usually in what some consider the lower socio-economic classes and seem to do poorly anyway in schools. Look at all the savings school districts could get by not having to spend tax dollars on a fuller education. If you look at this issue in a positive way, I'm sure you will begin to appreciate my points.

This is Â so sad that the air is polluted.I don't know how people are going to live like this now.If people smoke or if they don't that is bad for them and even for the kids!That is my opinion.But anyways its very very sad.

The saddest thing is that "recreational" pollution is increasing.Â Fire pits, wood barbecues, are huge sources of very unhealthy particulate pollution. Truly,we are doing this to ourselves.Â There are no rules.

This is Â so sad that the air is polluted.I don't know how people are going to live like this now.If people smoke or if they don't that is bad for them and even for the kids!That is my opinion.But anyways its very very sad.

The saddest thing is that "recreational" pollution is increasing.Â Fire pits, wood barbecues, are huge sources of very unhealthy particulate pollution. Truly,we are doing this to ourselves.Â There are no rules.

This is Â so sad that the air is polluted.I don't know how people are going to live like this now.If people smoke or if they don't that is bad for them and even for the kids!That is my opinion.But anyways its very very sad.

The saddest thing is that "recreational" pollution is increasing.Â Fire pits, wood barbecues, are huge sources of very unhealthy particulate pollution. Truly,we are doing this to ourselves.Â There are no rules.

Since 1998 it is known that ultrafine particles enter in the blood stream through the alveoli of the lung, cause mild inflammation, and are deposited in different organs, including the brain. Exposure to these is linked to CVD, some forms of cancer, and recently to diabetes and obesity. In a word, air pollution is responsible for many of non-communicable diseases. However, the medical establishment is motivated to treat the symptoms (forever), rather than addressing the cause. There is a proverb which says: "He is not crazy -- the one who eats the cake, but the one who grants it."Â It is up to the tax-payers, who pay the bill, to demand a paradigm change.

Since 1998 it is known that ultrafine particles enter in the blood stream through the alveoli of the lung, cause mild inflammation, and are deposited in different organs, including the brain. Exposure to these is linked to CVD, some forms of cancer, and recently to diabetes and obesity. In a word, air pollution is responsible for many of non-communicable diseases. However, the medical establishment is motivated to treat the symptoms (forever), rather than addressing the cause. There is a proverb which says: "He is not crazy -- the one who eats the cake, but the one who grants it."Â It is up to the tax-payers, who pay the bill, to demand a paradigm change.

Since 1998 it is known that ultrafine particles enter in the blood stream through the alveoli of the lung, cause mild inflammation, and are deposited in different organs, including the brain. Exposure to these is linked to CVD, some forms of cancer, and recently to diabetes and obesity. In a word, air pollution is responsible for many of non-communicable diseases. However, the medical establishment is motivated to treat the symptoms (forever), rather than addressing the cause. There is a proverb which says: "He is not crazy -- the one who eats the cake, but the one who grants it."Â It is up to the tax-payers, who pay the bill, to demand a paradigm change.

I suspect the fire pits and wood barbecues are not nearly as important a source as coal-fired power plants and burning gasoline and diesel fuel in vehicles.Â The paradigm changes must address how we generate electricity and move from one place to another.

I suspect the fire pits and wood barbecues are not nearly as important a source as coal-fired power plants and burning gasoline and diesel fuel in vehicles.Â The paradigm changes must address how we generate electricity and move from one place to another.

I suspect the fire pits and wood barbecues are not nearly as important a source as coal-fired power plants and burning gasoline and diesel fuel in vehicles.Â The paradigm changes must address how we generate electricity and move from one place to another.

Why, when mice stop swiming, is this not attributed to reduction in lung capacity caused by particulate pollution, and instead attriubted to depression?Â I imagine allÂ mice in captivity are depressed, but it seems more logical to consider reduced lung function in these particular mice who have been forced to breathe large quantities of particulate matter.Â The latter causes reduced lung function in humans.

Why, when mice stop swiming, is this not attributed to reduction in lung capacity caused by particulate pollution, and instead attriubted to depression?Â I imagine allÂ mice in captivity are depressed, but it seems more logical to consider reduced lung function in these particular mice who have been forced to breathe large quantities of particulate matter.Â The latter causes reduced lung function in humans.

Why, when mice stop swiming, is this not attributed to reduction in lung capacity caused by particulate pollution, and instead attriubted to depression?Â I imagine allÂ mice in captivity are depressed, but it seems more logical to consider reduced lung function in these particular mice who have been forced to breathe large quantities of particulate matter.Â The latter causes reduced lung function in humans.